216953657189 has 2 divisors, whose sum is σ = 216953657190. Its totient is φ = 216953657188.

The previous prime is 216953657099. The next prime is 216953657213. The reversal of 216953657189 is 981756359612.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 182965785025 + 33987872164 = 427745^2 + 184358^2 .

It is a cyclic number.

It is not a de Polignac number, because 216953657189 - 2²⁸ = 216685221733 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (216953657689) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108476828594 + 108476828595.

It is an arithmetic number, because the mean of its divisors is an integer number (108476828595).

Almost surely, 2^216953657189 is an apocalyptic number.

It is an amenable number.

216953657189 is a deficient number, since it is larger than the sum of its proper divisors (1).

216953657189 is an equidigital number, since it uses as much as digits as its factorization.

216953657189 is an evil number, because the sum of its binary digits is even.

The product of its digits is 24494400, while the sum is 62.

The spelling of 216953657189 in words is "two hundred sixteen billion, nine hundred fifty-three million, six hundred fifty-seven thousand, one hundred eighty-nine".